This research is a continuation of the development of a model that can be utilized in planning and monitoring the prehospital phase of an Emergency Medical Services (EMS) system. Emphasis is placed on determining policies for prehospital training (number and level) and skill maintenance in accordance with local and/or regional characteristics. This model will specify the training and continuing education options which maximize prehospital effectiveness subject to considerations of demand, type of response desired and cost. The model is characterized by components for which very little definitive information exists. The major part of this research responds to such questions. A randomized experiment has been designed to analyze the effect of skill maintenance and targeted continuing education on the EMS system. The first paramedic testing cycle has already been completed using a battery of tests to measure manual skills arryhtmia assessment and paramedic assessment and decisionmaking capability. The second testing cycle will be completed prior to the start of this continuation project. Continuing education methods include the development of computer scenarios and interactive video modules. Descriptive analyses will be used to analyze demand, type of response (single/dual tier, paid/volunteer, etc.), and cost. The prehospital care data system in Western Pennsylvania and the computerized algorithm performance measures developed in previous work will be major resources in effectively carrying out this project.